Piston ring



April 12, 1932. G, BUCHMANN 1,853,200

PISTON RING Filed April 12, 19:50

INVENTOR. WAQV q. DUCHMANN.

A TTORNEY.

modified form.

Patented Apr. 12, 1932 1 warren STATE-S EDWARD G. BUCHMANN, 0F DETROIT, MICHIGAN PISTON RING Application filed April 12,

This invention relates to piston rings, and is especially adapted and intended to be used on the pistons of internal combustion engines. q

The object of the invention is to provide a ring having improved'means for collecting oil from the cylinder wall. and returning the same to the crank case.

Another object of the invention is to provide improved means for seating the edges of the ring against the side walls of the groove. By side walls of the groove is meant the top and bottom walls when the piston is in vertical position.

A further object of the invention is to provide improved means for expanding a split ring against the cylinder wall.

A further object of the invention is to provide a. ring having a greater wall thickness than has heretofore been provided in rings of this general type. This greater thickness provides a relatively wide seating or contact surface against the side walls of the groove, and the greater the contact surface the more elfective is the seal between the ring and the side walls of the groove, and consequently the better it can hold compression and oil from passing behind and around the ring.

With these and other objects in view several forms of the invention are hereinafter described and are illustrated in the accompanying drawings in which Fig. 1 is a side elevation of one form of the ring. Fig. 2 is a section thereof. Fig. 3 is a section of the Fig. 4 is a section of a fur- Fig. 5 is a side elevation Fig. 6 is a detail in section is a plan view of a form ther modification. of another form. of Fig. 5. Fig. 7 shown in Fig. 5.

Referring to the forms shown in Figs. 1 and 2, the ring 6 is a transplit ring with a stepped joint at 7 permitting expansion and contraction. One edge 81's flat, to seat against the corresponding side wall of a groove in the piston. This will ordinarily be the top wall of the groove, in a vertical engine, or the groove nearest the cylinder head. At its opposits edge the ring is provided with a series of channels or slots 9'cut' therein, and these channels extend at an inclination inwardly 1930. SerialNo. 443,688.

from just inside the corner of the ring as v indicated at 10, which will be termed the inlet end of the channels, to the inside of the ring through which the channels open at the out let end llinto the ring groove.

The lower edge or surface of the ring, where it seats against the opposite side wall of the groove in the piston, is provided with c a series of curved orprojecting surfaces 12, which-correspond in number and position to the channels 9, and form spring members permitting axial compression of the ring. That is to say, when the ring is inserted in the groove it is compressed axially and slipped or forced into the groove with the result that the bowed 0r projecting portions 12 eX- ert a spring pressure against one side of the groove and force the surface 8 into close and I sealing contact with the upper or opposite wall of the groove, thereby making a very effective seal to prevent leakage or loss ofcompression around behind the ring.

Theoil collecting function of such a ring is this: The inlet 10 to the passages9 will ordinarily be adjacent, or possibly slightly uncovered at, the surface of the piston, and

on the outstroke of the piston the oil adhering to the surface of the cylinder will be scraped therefrom by the edge 0f' the ring: and will flow inwardly through the passages 9 into the ring groove, from which it may be drained back into the crank case by any suitable means, such for example as holes 13" (Fig. 7 extending through the piston wall from the bottom of the ring groove.

It will be noted that the ring provides a wide hearing or seal between the surface 8 and the-side wall of the groove, and also provides means for permitting axial compression of the ring and for collecting oil from the cylinder wall.

The form shown in Fig. 3 is the same as that shown in Fig. 2, with respect to the passages 9, but instead of having a bowed or projecting surface 12, the 1 corresponding. surface or. edge leis made straight, or parallel to the surface-8. This form has the same functions with respect to the wide'bearing and the oillcollecting feature as that above described, and also provides a wide bearing at both edges 8 and 14.

In the form shown in Fig. 4 the same oil collecting passages 9 are provided, extend- 5 ing through the ring from one edge or side wall thereof, at an inclination, to the inside of the ring, but in this form the inside surface of the ring is channeled or cut away to produce a channel extending completely around the ring, the bottom of the channel being indicated at 15, and-beveled at its edges as indicated at 16, to the opposite surfaces or edges of the body of the ring. And in this form is provided means to expand the ring, consisting of a corrugated spring 17 (shown also in 7 )j: which is inserted in the channeli and bears against the bottom 18 of the groove in the piston. This spring tends to expand the ring after it is inserted in the groove and hold its other wall in close contact with the cylinder wall, the ring being transplit, as indicated above, to permit exnsion or compression. This form retains the wide bearing; and oil collecting features above described.

In the modified form shown in Figs. 5 and 6- the ring 611, instead of having the inclined grooves 9,. has a series of staggered grooves 19,.showrm arranged in two lines, these grooves extendingthrough the ring from the outer to: the inner surfaces and communicating at their inner ends with the channel on the inside; of the ring the bottom of which is in- (heated at 15a and: the beveled edges of which are: indicated at 1607. And this form is provided. with a corrugated expanding spring 17 as above described. Also, this form may a tongue joint, where it: is transplit, as indicated at 20, instead of the stepped joint 7. This: form, it will. be noted, has a wide hearing at. top and bottom, and the slots 19 sem to permit the flow of oil inwardly thmough the ri'ngto the bottom of the groove from which it, can return to the crank case though the holes 131 The invention may be: embodied in various other forms within the scope thereof, and no limitation in: this respect is implied.

I claim:

1. A transplit piston ring having a series of slots, extending their whole length from theinner surfiace of the ring through the edge of said ring-and. nearly the whole circumferenceof the ring 2. A piston. ring as set forth in claim 1, the opening of the slotsithrough the edge of the r ng being close t-o'the outer periphery of the ring so as to collect oil from nearly the whole circumference of a cylinder wall.

3.. A transplit piston ring having a series of slots extending from the inner surface of the ring to and through one edge of the ring the opening through said edge being wholly inside of the peripheral surface of the ring.

4. A transplit piston ring as in claim 3, and

one edge of the ring having a series of projections to produce axial expansion of the ring.

5. A transplit ring as in claim 3, in combination with a spring within the ring to expand the same and hold said peripheral surface in contact with a cylinder wall.

6. A transplit ring having a series of slots extending from the inner surface of the ring through to and connecting with a groove at one edge of the ring, said groove being wholly inside of the periphery of the ring, one edge of said ring having a series of projections to produce axial expansion of said ring.

7. The combination stated in claim 6, the inner side of the ring being channeled, and an expansion spring in contact with the bottom of said channel.

8. The combination as stated in claim 6 and an expansion spring having contact with the ring and the bottom of the ring groove.

In testimony whereof, I do aflix my signature.

EDWARD G. BUCHMANN.

Iii; 

